I like to know should i upgrade my HD5850 1G or C2d e7600 3.0Ghz to get better fps and graphic for new games like Farcry 3. I like to get a new cpu maybe i3/i7 but that means i have to change a few other things like mb etc which i can't afford. Or are they good enough to get the beauty of the Farcry 3?

For your information the average fps that i've managed to get with older shooter games are about 30-40 with moderate setting. I'm looking for 40+ and most importantly a bit higher setting if i could for future games. Can someone recommend what Graphic card should i upgrade to with minimal price.

Have you tried OC your E7600?
That's the cheapest free way to improve performance.
According with your system specs you have a p35 mobo, right?
I think with that mobo your E7600 could be easily overclocked to 3.6 GHz or higher with the proper cooling.

5850 is still a good card.
If you upgrade it to a newer one and more powerfull card, then you could find that new card would be bottlenecked by current cpu.-

Edit:Do the math!
A real upgrade over 5850 could be at least hd7850/gtx660.
With the money you spend on a new gfx card you can buy h77 matx mobo + i3 2120 + 8gb ddr3 1333mhz which is a great upgrade over your current system

Cheapest way to improve your fps oc the cpu first then the gpu but that cpu is kinda weak being just an dual core so you should think about upgrading to something like a i5 3750k +z77 mobo or 2500k +z68 if you find one cheaper that 5850 is stll ok.

Guys thank u very much for all the suggestions and option. Everything looks clear to me now, at least. I'm not into overclocking because climate reason and not kinda techie person. And changing cpu/mb/ram i think is more future proof, personallly. I will get the most minimal cost for those (with i5 cpu) and use the 5850 instead. Tq guys.

While OCing the CPU will give you a bit of a boost, you'll need to put at least $20 into an aftermarket cooler, and it will still be just a dual core. More and more top games released make use of quad core tech, it can make quite a difference. There's also some CPU, MB, RAM bundles this time of year that are tempting if you can afford to buy now.

I say save that cooler money and put it toward a better CPU, MB and RAM. One way you can assess how much performance each component adds to the overall system is by running the Windows Experience Index bench, but in your case just playing any resource intense made for quad game would make it obvious that the CPU is the bottleneck in that build.